Dubstep Man

Mariachi

The perpetual motion hamster.

Mariachi is a robot hamster that appeared in Mega Man #9. He was created by Dr. Light for unknown purposes, though "for fun" cannot be ruled out. As Mariachi runs, his wheel charges a battery, and the battery powers Mariachi, creating a perpetual motion machine. Proto Man then tells Mega Man, "And people wonder why I didn't want him messing with my power supply."

Its name is most likely a reference to the Mexican genre of music, continuing the theme of the original series Mega Man characters being given music-related names.

Origami Man

Origami Man.

Origami Man is a Robot Master in Mega Man #17 created by Dr. Wily, which was soon scrapped due to his sole ability to transform into origami.

Poorly Conceived Robot Masters

Ick...

The Short Circuits from Issue 49 introduces four poorly conceived Robot Masters:

UGH-001 I Can't Find My Keys, Man! - A robot slightly similar to KeyMan that isn't able to find his keys.

ICK-002 Itch Man - A very itchy robot with multiple arms, which he uses to scratch himself.

ACK-003 Motion Sickness Man - A robot with several spirals in his body that doesn't feel well.

MEH-004 Fragile Man - A very fragile robot that appears broken in pieces.

Trivia

In the second issue of the comic, Mega Man asked Dr. Light why he couldn't "make Origami Man or Pillow Man" when he is going to fight against Bomb Man.

Origami Man may be inspired by the recurring joke of a paper-themed Robot Master creating a cycle, thus creating "Rock" (Rockman, Mega Man's original name in Japan, and also Guts Man), "Paper", and "Scissors" (Cut Man).